Electric valve converting system



Oct. 5, 1937.

c. A. SABBAH ELECTRIC VALVE CONVERTING SYSTEM Filed July 8, 1956 I Fig.l.

FREQUENCY VAR YING nzms Inventor. Cami! A. Sabbah, Deceased b Wiiliam A.Dodge, Administrator ttorneg.

Patented Oct. 5, 1937 PATENT OFFICE 2,094,821 ELECTRIC VALVE CONVERTINGSYSTEM Camil A. Sabbah, deceased, late of Schenectady, N. Y., by WilliamA. Dodge, administrator,

Schenectady, Company, a

N. Y., assignor to General Electric corporation of New York ApplicationJuly 8, 1936, Serial No. 89,593

'9 Claims.

This invention relates to electric valve converting systems and moreparticularly to such systems suitable for transferring energy from onedirect current circuit to another.

An electric valve converting system suitable for transferring energybetween'constant poten- .tial and constant=current direct currentcircuits is disclosed in United States Letters Patent No.

1,961,080 granted May 29, 1934, upon the application of C. A. Sabbah.The apparatus disclosed therein utilizes a three-legged reactor hav inginductive windings on the several legs thereof and an energy storagedevice or capacitor associated with at least a portion of the inductivewinding on each leg.

One of the objects of this invention is to provide an improved electricvalve converting system of this type utilizing a minimum of apparatusand which will be simple and reliable in operation.

The novel features which are believed to be characteristic of thisinvention are set forth with particularity in the appended claims. The

invention itself, however, both as to its organlzation and method 'ofoperation, together with I 'further objects and advantages thereof, willbe better understood by reference to the following description taken inconnection with the accompanying drawing in which Fig. 1 represents thepreferred embodiment of the invention and Fig; 2 is a modification ofthe invention utilizing a 'multi-anode single-cathode electric dischargevalve.

Referring now more particularly to Fig. 1 of the drawing, there isillustrated an electric valve converting system for transferring energybetween a constant potential direct current circuit IO, N and a constantcurrent direct ourrentcircuit I2, said circuits having a common terminalII. This system is provided with an energy storage and transfer devicecomprising a two-legged magnetic core structure l3 represented by dottedlines and having a pair of inductive windings I4, I5; and l6, I! on eachleg thereof, each pair of inductive windings being provided with anenergy storage device which may be in the form of capacitors l8 and I9.One of the windings of each pair of windings is associated with anenergy storage device such as capacitors l8 and I9 which may beconnected in parallel with windings l4 and I6 respectively. One terminalof each of the windings l4 and I6 is connected directly to one side ofthe constant potential direct current circuit II), II and the otherterminal of these windings is connected by means of the pair of valves20, 2| to the other side of the constant potential direct currentcircuit III, II. The remaining. windings l5 and I1 are each connectedwith one terminal to one side of the constant current direct currentcircuit I2 and with the remaining terminal to the other side of theconstant direct current circuit |2 by means of the electric valves 22,23. In order to prevent any reaction between the electric valveconverting apparatus 10 and the direct current circuit, the smoothinginductors 24, 25 may be connected between the apparatus and the lineconductors in, II. While each of the valves 20, 2|, 22 and 23 is shownas being provided with an anode, a cathode and a ll control grid, thesevalves may be any of the sev-' eral types well known in the art,although it is preferable to utilize valves of the type containing anionizable medium and which are provided with control or startingelectrodes whereby the 20 discharge paths between the anodes andcathodes may be controlled. The control electrodes 01' grids of thevalves 20, 2|, 22- and 23 are energized from a suitable source ofalternating current 26 by means of transformers 21 and 28. The source ofalternating current 26 is preferably derived from a generator or anoscillator, the frequency of which maybe readily varied. In accordancewith the customary practice the value of the grid current in the controlcircuit may be limited by inserting therein the resistors 29, 30, 3| and32. In order to provide a means for controlling the phase relationbetween the alternating potential impressed upon the grid circuits ofthe valves 22 and 23 and that impressed upon 35 the grid circuits of thevalves 20 and 2| a phase shifting circuit comprising a reactor 33, acapacitor 34 and a variable resistor 35 is interposed between thetransformer 21 and the alternating current source 26. While there isshown a plu- 40 rality of valves, it will be apparent to those skilledin the art that a double-anode, single-cathode valve may be used toreplace the valves 2| and 22 and likewise another such valve could besubstituted for valves-22 and 23. 4

In operation, neglecting the leakage reactance between the windingscommon to each leg of the device l3, the windings and capacitors as--sociated with this core structure serve to maintain the totalmagnetomotive force and that of each of the legs of the magnetic corestructure I3 at a substantially constant value. Each of the valves isconductive for a period equal to 180 electrical degrees. During the timethat electric valve 20 is conductive electrical energy is stored in thecircuit comprising the inductor winding I 4 and the capacitor l8. Afterthe electric valve 20 has been conductive for 180 electrical degrees thecurrent is transferred. from this valve to valve 2| which now causesenergy to be stored in the inductor winding I 5 and the capacitor l9. Bymeans of the phase shift circuit, the time of the initiation ofconductivity of the valves 20 and 2| is so arranged that each of thesevalves becomes conductive sometime after valves 22 and 23, respectively,were rendered conductive. This time interval may? be any value slightlygreater than zero degrees and slightly less than 180 degrees. It will beobvious, of course, to those skilled in the art that the system will notoperate satisfactorily when the time of ignition of valve 20 is eitherin phase with the ignition of valve 22 or exactly out of phase withvalve 22 because of the constant current output characteristic of theapparatus. It is believed that the above explanation presents inaccordance. with present knowledge the most likely theory of operationof the circuit arrangement disclosed herein, although there may be otherexplanations and the above is not to be construed in a limiting sense.

The size of the capacitors i 8, IS, the ratio of the windings l4, IE totheir-respective associated windings l5, H, the phase relation betweenthe control potentials applied to the pairs of valves 20, 2|, and 22,23, and the frequency of the alternating current circuit 26 'alldetermine the amount of power transferred between the direct currentcircuits. By providing means (not shown) for varying the frequency ofthe source of potential 26, the value of the energy transferred betweenthe two circuits may be readily controlled. While the operation of thecircuit disclosed has been described in terms of transferring power fromthe constant potentialdirect current circuits l0, II to the constantcurrent circuits ll, l2, it will be apparent to those skilled in the artthat energy may be transferred from the constant current direct currentcircuit to the constant potential direct current circuits In Fig. 2there is disclosed'an arrangement utilizing a four-anode, single-cathodeelectric valve discharge device 33 in place of the four individualelectric valves of Fig. 1. Since the remaining components of the systemare identical to that disclosed in Fig. 1 they have been given likereference numerals. It will be noted, however, that the conductor 12 inFig. 2 is now connected to the inductive windings l5 and I1 whereas inFig. 1 the conductor I2 was connected to the cathodes cf the valves 22and 23.

It will be remembered, however, that in connec-.

l2 by means of conductive connections and the equivalent of the electricvalves 22 and 23. Since the same control electrode circuit of, Fig. 1may be utilized in the control of the discharge valve 33 of Fig. 2 thiscontrol circuit has been indicated very schematically by the grids butthe detail grid circuits have been omitted.

understanding of this embodiment of the invention.

While this invention has been shown and described in connection withcertain specific embodiments it will, of course, be understood that itis not to be limited thereto, since it is apparent that the principlesherein disclosed are susceptible of numerous other applications, and

modifications may be made in the circuit arrangements and in theinstrumentalities employed without departing from the spirit and scopeof the invention as set forth in the appended claims.

What is claimed as new and desired to be secured by Letters Patent ofthe United States is:

2. An electric valve converting system for transmitting energy betweentwo circuits, one of which has a constant current characteristic,comprising a two-legged magnetic core structure provided with a windingfor each leg,a capacitor for each winding connected in parallel thereto,means including an electric discharge valve means interconnecting thewindings of said structure with said circuits, and means for controllingthe sequence and the frequency of the conductivities of said valvemeans. 1

3. An electric valve converting system comprising direct current inputand output circuits, a two-legged core structure provided with a pair ofwindings on each leg, electric discharge valve ,means interconnectingone winding of each of said pair of windings with one of said directourrent circuits, other electric discharge valve means interconnectingthe remaining windings with the other of said direct current circuits, acapacitor for each of the windings associated with one of said circuits,said capacitors being connected in parallel with their respectivewindings, and means for controlling the conductivities of said valvemeans.

i 4. An electric valve converting system comprising direct current inputand output circuits, one of said circuits having a constant potentialcharacteristic and the other a constant current characteristic, atwo-legged magnetic core structure provided with a pair of windings oneach leg, electric discharge valve means'interconnecting one of thewindings on each leg with one of said circuits and the remaining windingon each leg with the other of said circuits, a capacitor connectedacross each winding associated with said constant potential circuit, andmeans for controlling the conductivities of said valve means.

5. An electric valve converting. system for transferring energy betweentwo circuits, one'of said circuits being a' constant current circuit,comprising a two legged magnetic core structure having at least'oneinductive winding on each leg thereof, an energy storage deviceassociated with the inductive winding on each leg to maintain asubstantially constant magnetomotive force in said structure, electricvalve means interconnecting said windings of said structure with saidcircuits, means for controlling the conductivity of said valve means,and means for controlling the frequency at which said valve means becomeconductive. 1

6. An electric valve converting system comprising direct current inputand output circuits, a two-legged core structure provided with a pair ofwindings on each leg, electric discharge valve means interconnecting onewinding of each of said pair of windings with one of said direct currentcircuits, other electric discharge valve means interconnecting theremaining windings with the other of said direct current circuits,'a capcitor for each of the windings associated with o e of said circuits,said capacitors being connected in parallel with their respectivewindings, and means for alternately initiating the conductivities of thevalve means associated with each'leg of said structure.

7. An electric valve converting system for transferring energy between aconstant potential direct current circuit and a constant current directcurrent circuit comprising a two-legged magnetic core structure, a pairof windings for each leg thereof, a plurality of energy storage deviceseach associated with one of the windings of each leg, means including anelectric discharge valve means for each winding of said structure forinterconnecting said windings with said circuits, and means foralternately initiating the conductivities of the valve means associatedwith each leg of said structure and for controlling the time intervalbetween said initiations of conductivity.

8. An electric valve converting system for transferring energy between aconstant potential direct current circuit and a constant current directcurrent circuit comprising a two-legged magnetic core structure, a pairof windings for each leg thereof, a plurality of energy storage deviceseach associated with one of the windings of each leg, means includingelectric discharge valve means for interconnecting each of said windingswith said circuits, and means for alternately in- I itiating the periods01' conductivity of the valve means associated with each leg so thatsaid periods are concurrent for a portion of each cycle of operation.

9. An electric valve converting system for transmitting energy betweendirect current circuits, said system having input and output.circuitsone of which has a constant current characteristic, comprising atwo-legged magnetic core structure provided with a pair of windings foreach leg, a capacitor connected in parallel with one winding of eachleg, electric discharge valve means provided with control electrodes andinterconnecting the windings of said structure with said direct currentcircuits, means for alternately energizing the control electrodes of thevalve means associated with the windings on each leg of said structure,and means for controlling the frequency of the energization of saidcontrol electrodes. a

WILLIAM A. DODGE, Administrator of the Estate of Cami! A. .S'abbah,

Deceased.

